Department of Plant Pathology & Microbiology, University of California, Riverside, CA 92521-0122, United States.
Department of Plant Pathology & Microbiology, University of California, Riverside, CA 92521-0122, United States.
Virology. 2014 Feb;450-451:222-32. doi: 10.1016/j.virol.2013.12.008. Epub 2014 Jan 7.
The phenomenon of rapid turnover of 3' proximal nucleotides (nt) lost by the action of nuclease in RNA viruses is integral to replication. Here, a set of six deletions encompassing the 3' 23 nt region of a satellite RNA (satRNA) of Cucumber mosaic virus (CMV) strain Q (Q-sat), were engineered. Repair of the 3' end was not observed in the absence of CMV. However, co-expression with CMV in planta revealed that Q-sat mutants lacking the 3' 18 nt but not the 3' 23 nt are repaired and the progeny accumulation was inversely proportional to the extent of the deletion. Progeny of the 3'Δ3 mutant were repaired to wild type (wt) while those from the remaining four mutants were heterogeneous, exhibiting a wt secondary structure. Analysis of additional 3' internal deletions mutants revealed that progeny with a repaired sequence reminiscent of wt secondary structure were competent for replication and systemic spread.
在 RNA 病毒中，核酸酶作用导致 3' 近端核苷酸（nt）快速丢失的现象是复制的一个组成部分。在这里，设计了一组包含黄瓜花叶病毒（CMV）菌株 Q 的卫星 RNA（satRNA）3' 23 nt 区域的六个缺失。在没有 CMV 的情况下，没有观察到 3' 端的修复。然而，在体内与 CMV 共表达时发现，缺失 3' 18 nt 但不缺失 3' 23 nt 的 Q-sat 突变体被修复，并且后代的积累与缺失的程度成反比。3'Δ3 突变体的后代被修复为野生型（wt），而其余四个突变体的后代是异质的，表现出 wt 的二级结构。对其他 3' 内部缺失突变体的分析表明，具有类似于 wt 二级结构的修复序列的后代能够进行复制和系统传播。
